Effects of cooling rate on post-thaw motility and fertility of Japanese pearl oyster <Emphasis Type="Italic">Pinctada fucata martensii</Emphasis> spermatozoa

The post-thaw motility and fertility of Japanese pearl oyster sperm show large variances, even among sperm samples obtained from the same individuals. This study aimed to clarify the factors that cause such differences. Spermatozoa were diluted 50 times with diluent comprising 10 % methanol, 18 % fetal bovine serum, and 72 % seawater, and dispensed into 0.25 ml straws. A total of 59 straws were cooled, one by one, at 11 different heights from the surface of liquid nitrogen (LN) to −50 °C, and then immediately immersed in LN. After thawing the straws, the relationships between the cooling rate and the post-thaw motility and post-thaw fertility of the spermatozoa were examined. Both the post-thaw motility and the post-thaw fertility showed a sharp peak when the straws were cooled at around −20 °C/min. There was a strong correlation between post-thaw motility and fertility (P < 0.001). There was a large difference in the cooling rates and the post-thaw motilities and fertilities of the spermatozoa, even between straws cooled at the same height. These results indicate that the optimum range for the cooling rate of oyster spermatozoa is quite narrow, and the method of cooling straws at a fixed distance from the LN surface is unsuitable for the cryopreservation of Japanese pearl oyster spermatozoa.     

Growth,nutrient utilization,oxidative condition,and element composition of juvenile red sea bream <Emphasis Type="Italic">Pagrus major</Emphasis> fed with fermented soybean meal and scallop by-product blend as fishmeal replacement

A feeding trial was conducted to evaluate the effect of fermented soybean meal and scallop by-product blend (3:2) (FP) on the performance of juvenile red sea bream. Five isocaloric diets were prepared by replacing 0% (FP0), 15% (FP15), 30% (FP30), 45% (FP45), and 60% (FP60) fishmeal (FM) protein with FP, respectively. Triplicate groups of fish (initial mean weight 2.83 g) were fed the test diets for 45 days in a flowthrough seawater system. The results demonstrated that growth rates of fish fed FP0, FP15, and FP30 were similar, and significantly higher (P < 0.05) than those of FP45 and FP60. Nutrient utilization was significantly lower in FP60, with no differences found among the other groups. Dietary heavy-metal contents were affected by inclusion of FP, impacting on whole-body heavy-metal contents. In terms of oxidative stress, fish fed the FP30 diet were in the best condition, since this fish group showed the least oxidative-stressed condition as well as the highest tolerance against oxidation. In conclusion, the approach of utilizing this fermented mixture is promising and it could replace at least 30% FM protein in red sea bream diet without negative effects on performance, body composition or health of fish.     

Isolation of canine C-reactive protein and characterization of its properties

C-reactive protein (CRP) was isolated from the acute phase serum of dogs subjected to surgical stimulation. Its properties were characterized. Canine CRP was isolated by ion-exchange chromatography using DEAE-Sephacel and DEAE-Sephadex A-50 and affinity chromatography using protein A-Sepharose CL 4B in combination with agar-block electrophoresis. In immunoelectrophoresis, canine CRP had the same γ-mobility as human γ-type CRP. The molecular weight of purifined canine CRP was estimated by gel filtration and sodium dodecyl sulfate polyacrylamide gel electrophoresis to be approximately 157 000 and 155 000 respectively. This CRP was a thermolabile protein which completely lost its antigenicity by heating at 70°C for 15 min. The serum concentration of CRP in normal beagle dogs ranged from 0.198 to 0.826 μg ml⁻¹ (0.486±0.170 μg ml⁻¹). The concentration was acutely increased by surgery as it was in man and was rapidly decreased with convalescence. Dogs can be a useful animal model for investigation of the mechanism of CRP production and the function of CRP.     

Two‐Year Follow‐Up Magnetic Resonance Imaging and Spectroscopy Findings and Cerebrospinal Fluid Analysis of a Dog with Sandhoff's Disease

A 13‐month‐old female Toy Poodle was presented for progressive ataxia and intention tremors of head movement. The diagnosis of Sandhoff's disease (GM2 gangliosidosis) was confirmed by deficient β‐N‐acetylhexosaminidase A and B activity in circulating leukocytes and identification of the homozygous mutation (HEXB: c.283delG). White matter in the cerebrum and cerebellum was hyperintense on T2‐weighted and fluid‐attenuated inversion recovery magnetic resonance images. Over the next 2 years, the white matter lesions expanded, and bilateral lesions appeared in the cerebellum and thalamus, associated with clinical deterioration. Magnetic resonance spectroscopy showed progressive decrease in brain N‐acetylaspartate, and glycine‐myo‐inositol and lactate‐alanine were increased in the terminal clinical stage. The concentrations of myelin basic protein and neuron specific enolase in cerebrospinal fluid were persistently increased. Imaging and spectroscopic appearance correlated with histopathological findings of severe myelin loss in cerebral and cerebellar white matter and destruction of the majority of cerebral and cerebellar neurons.     

Lactic acid bacteria effective for regulating the growth of contaminant bacteria during the fermentation of <Emphasis Type="Italic">Undaria pinnatifida</Emphasis> (Phaeophyta)

ABSTRACT:   Lactic acid fermentation of seaweed is a recent topic and quite limited information is available on culture conditions. To know the suitable strains for use as a starter culture for seaweed fermentation, 14 lactic acid bacteria (LAB) strains, including 11 species, were tested in culture conditions prepared with or without salt. A commercial product of Undaria pinnatifida powder was used as a substrate for fermentation without sterilizing. Starter-suitability of the LAB strains was assessed from their predominance after culture. Among the tested strains, Lactobacillus brevis, Lactobacillus plantarum, Lactobacillus casei and Lactobacillus rhamnosus showed high (>90%) predominance in their cultures, while control cultures prepared without inoculation of LAB did not show any detectable growth of acid producing bacteria and spoiled. A total of 102 strains not showing acid producing activity were isolated and characterized from spoiled cultures, and all the isolates were observed as Bacillus strains, including 64 strains (62.7%) and 16 strains (15.7%) of a Bacillus cereu s-related and B. fusiformis -related species, respectively. The Undaria substrate before fermentation contained culturable microorganisms at 1.4–3.1 × 10² CFU/g, but the Bacillus cereu s-related strain was not a major composition, suggesting a concern of selective growth of the Bacillus cereu s-related strain during the spoiled fermentation.     

Nodal, uterine and meningeal gamma(delta) T-cell lymphomas in cattle

Three cases of bovine gamma(delta) T-cell lymphoma without skin involvement are described. Case 1 was a 17-month-old Holstein heifer with generalized lymphadenopathy. Case 2 was a 4-year-old Holstein cow that had multiple tumour masses in the uterine body and horns. Case 3, a 23-month-old Holstein bull was presented with generalized tremor, nystagmus and hyperesthaesia, and there were several tumour masses in the meninges. Cases 1 and 2 had epitheliotropic neoplastic infiltrates in the tonsillar epithelium and endometrial glands, respectively. Immunohistochemistry showed CD3+, WC1+, CD79a- lymphoma cells in all cases, and perforin was positive in two cases. Electron-dense granules were present in many neoplastic cells of all cases. These findings supported the cytotoxic gamma(delta) T-cell origin of the present lymphomas. Bovine gamma(delta) T-cell lymphoma may originate in a wide variety of anatomical sites and may be classified into several histological subtypes.     

Lineage classification of canine inheritable disorders using mitochondrial DNA haplotypes

To estimate the maternal effects of dog breeds using mitochondrial DNA(mtDNA) haplotypes in the dogs with several clinical disorders, 600 base pairs of mtDNA D-loop region were amplified from 365 dogs and were determined for mtDNA sequences. The diversity of the 600-bp sequences was classified into 64 haplotypes, including 46 newly discovered haplotypes, and the haplotypes were grouped into four clusters I to IV. Lineage analysis using the mtDNA haplotype indicated that each dog breed genetically comprises one or a few mtDNA haplotypes. When the relationship between genetic background and occurrences of clinical diseases was estimated, canine lineage analysis using mtDNA haplotype revealed that the disorders distributed in the dominant mtDNA haplotypes of each dog breed, but no disorder closely associated with mtDNA haplotypes was detected.     

Development of an on-site plum pox virus detection kit based on immunochromatography

Sharka disease, caused by plum pox virus (PPV), is the most serious viral disease of stone fruit trees. Among the eight known strains of the virus, PPV-D is the most important due to its recent global spread. Although enzyme-linked immunosorbent assay (ELISA) is the most common approach for diagnosing sharka, it involves time-consuming steps and requires expensive equipment and trained technicians. In this study, an on-site PPV detection kit based on immunochromatography was developed using polyclonal antibodies against the coat protein (CP) of a PPV-D isolate. The immunochromatographic (IC) assay kit was as sensitive as a commercial ELISA system for detecting Japanese PPV-D isolates. Moreover, it was easy to use (a one-step procedure), and results could be obtained on-site within 15 min without special laboratory equipment. The IC assay kit detected the virus from every aerial part of symptomatic Japanese apricot trees. In a detailed study of viral localization in leaves, the most suitable plant parts for use in the IC assay were symptomatic mesophyll tissues and the region from the petiole to the main vein. A positive reaction was also observed using the CP of other major (PPV-M and PPV-Rec) and minor (PPV-EA, PPV-W, and PPV-T) strains.     

Evaluation of Meat and Bone Meal as Replacement for Protein Concentrate in the Practical Diet for Sutchi Catfish,Pangasius hypophthalmus (Sauvage 1878), Reared under Pond Condition

An 80‐d feeding trial was conducted to evaluate meat and bone meal (MBM) as replacement of protein concentrate (PC) in practical diets for sutchi catfish, Pangasius hypophthalmus. Triplicate groups of juvenile sutchi catfish (initial weight 4.80 g) were stocked at the rate of 20,000 fish/ha in 12 earthen ponds (30 m² each). Four isocaloric diets (4.12 kcal/g) were formulated by replacing 0 (Diet 1, control), 33 (Diet 2), 67 (Diet 3), and 100% (Diet 4) PC protein with MBM. The growth parameters [final weight, % weight gain, and specific growth rate (SGR)] of fish fed Diets 1, 2, and 3 were not significantly different (P > 0.05) from each other but were significantly (P < 0.05) higher than those in Diet 4. The protein content in fish fed Diet 4 was significantly (P < 0.05) lower than the others. The total production of fish in different treatments ranged between 1917 and 2648 kg/ha/80 d. A simple economic analysis determined that the highest net profit (Tk. 52,965/ha) was obtained with Diet 2 and the lowest (Tk. 27,127/ha) with Diet 4 having 100% PC protein replacement. From the results of the study it is concluded that MBM can substitute up to 67% PC protein in catfish diet without hampering the growth and feed utilization.